Conventionally, as disclosed in a Japanese Patent Laid-Open No. H07-46676 (patent document 1), an electronic control device installed in a vehicle, or an in-vehicle Electronic Control Unit (ECU) performs, in cooperation with an external diagnosis device (i.e., a so-called diagnosis tool), an off-board diagnosis of a vehicle, in response to a request from the external diagnosis device. In such an off-board diagnosis, a read-out instruction is sent from the diagnosis tool to the in-vehicle ECU to read out various failure diagnosis data including a result of an on-board diagnosis, or to control the vehicle devices for various operations that are not usually performed, in order to perform a high-level diagnosis.
Further, in recent years, vehicle manufactures sometimes provide a remote diagnosis service for the vehicle user. The remote diagnosis service may, for example, collect data such as a travel distance, a failure diagnosis data, warning information, and the like from each vehicle to send to a management center via a data communication, and may send a notice to the user based on the collected data that it is time for the vehicle to have a regular checkup in a service shop, for example.
When the off-board diagnosis is performed in response to a request from the diagnosis tool, the diagnosis tool is connected to a dedicated connector, and the request is sent in a message form to the in-vehicle ECU via a dedicated connector. The in-vehicle ECU sends back a response message to the diagnosis tool within a preset period of time, after receiving a request message. The diagnosis tool determines that an abnormality is being caused regarding a communication with the in-vehicle ECU, if the tool does not receive the response message within the preset period of time.
Therefore, to provide the remote diagnosis service described above, a special care is required to not delay a process of the off-board diagnosis that is performed based on the request from the diagnosis tool. Therefore, to prevent such a delay, when the diagnosis tool is connected to the dedicated connector, the in-vehicle ECU may be configured not to perform a process about the remote diagnosis service.
However, a publicly-sold display device is connectable to the dedicated connector for reading various kinds of vehicle information (e.g., for reading a fuel mileage, an average speed, water temperature etc.,) and the user can purchase such a device in an aftermarket. The display device is, in principle, connected to the dedicated connector all the time, for the reading of the vehicle information. On the in-vehicle ECU side, it is difficult to distinguish whether the connector is connected to the diagnosis tool or to the display device. Therefore, if the in-vehicle ECU is configured not to perform the process about the remote diagnosis service when an external device is connected to the dedicated connector, the data required for the remote diagnosis service is not transferable from the vehicle to the management center when the user connects the above-described display device to the dedicated connector.